Ive had the same problem with it. It seems to be some kind of glitch, the only way ive found around it is to just switch the channel you record to. Starting a new project can help to. Ive also had the problem where it will record both inputs to both channels, so they both sound the same, dont know why!

Steve68 wrote: I recorded a track and then tried to record a guitar track using an effect I found in the DP-01. Sounded great and it recorded fine, but when I played it back, the great guitar sound wasn't there.

You can't "fix" this. It is a feature. You'll find that most mixers, DAWs, All-in-one recorders work in a similar manner. They do this so that you can be sure to get a good signal to disk without comprimising it by using the effects. You can always add effects after the fact but once they're on disc, you can't remove them. What I would do is keep a log of the effects you use for each channel as well as the parameter settings. You should really be doing this anyway. It's good practice and something you will have to do should you want to persue this in a pro studio environment. (The console gets zeroed before you leave. Sometimes there's a charge for every fader/button and nob not returned to 0).

I have four tracks recorded.  I would like to use an external effects processor to add an effect to one of these tracks.  Can I mute three of the recorded tracks, then connect the output of the vocal track into my external effects processor and route the stereo outputs of the processor to newly assigned tracks on my DP 01 FX/CD and record?